1. [n]  belongs to lowest social and ritual class in India
2. [adj]  not capable of being obtained; "a rare work, today almost inaccessible"; "timber is virtually unobtainable in the islands"; "untouchable resources buried deep within the earth"
3. [adj]  defiling to the touch; especially used in traditional Hindu belief of the lowest caste or castes
4. [adj]  forbidden to the touch; "in most museums such articles are untouchable"
5. [adj]  impossible to assail
6. [adj]  beyond the reach of criticism or attack or impeachment; "for the first time criticism was directed at a hitherto untouchable target"- Newsweek

Untouchable
Although Robert De Niro has fiercely protected his private life, film scholar Andy Dougan manages to dig up some personal details drawing on his interviews with De Niro himself and some of the actor`s acquaintances. In doing so, he chronicles the acclaimed actor`s rise to fame and entertains popular rumors, including the gossip that De Niro participated in a test-tube experiment that resulted in the birth of twin boys.

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